Create reports in Search Ads 360 that compare performance before and after after launching the Search Ads 360 bid strategy.
This is the easiest comparison to set up, but the result is significantly affected by extrinsic factors, such as competitors, seasonality, and so on. In other words, this comparison may give a general idea of the relative merits of automated and manual bidding, but it's not a rigorous comparison.

Compare similar campaigns or compare by geography:

Compare campaigns managed by a Search Ads 360 bid strategy to similar campaigns that are not managed by a bid strategy (or that are managed by some other bidding system).
This comparison ensures that both types of campaigns experience the same extrinsic factors, so it's better than comparing pre-launch and post-launch performance. However, it's only effective if you have truly similar campaigns that you can compare.

Run a Search Ads 360 bid strategy experiment that compares similar geographic regions.
If you have campaigns with the same keywords and ads but are targeted to different geographic regions, you can apply a Search Ads 360 bid strategy to campaigns in one region, but not the other. When you compare performance, you can almost completely eliminate differences due to extrinsic and intrinsic factors.

This is the recommended way to compare performance if you're able to target campaigns to separate geographical regions.

Important

Test one change at a time. During a test, don’t change creatives, landing pages, campaign settings, etc. You want to minimize the number of variables that are changing during the test period. Otherwise, if you change both your bid management from manual to a Search Ads 360 bid strategy, and change your landing pages, you won’t know if the conversion volume changed because of the landing pages or due to the bid strategy optimizing your bids.

Compare pre-launch to post-launch

Create reports in Search Ads 360 that compare performance before launching the Search Ads 360 bid strategy with performance after the launch:

From the View menu that appears just below the tabs, select one of the following:

Performance if you're comparing a bid strategy with a clicks or position goal.
In addition, if you're comparing the position goal, add the Position column to the report.

Action if you're comparing a bid strategy with a CPA target.

Sales if you're comparing a bid strategy with a ROAS or ERS target.

Click the time-range selector that appears in the upper right corner of the page and do the following:

From the Time range list, select Custom.
Specify a starting date that's at least 4 weeks after you launched the bid strategy, and at least 2 weeks since you've made any changes to the bid strategy's target amount.

Specify an end date that's at least 2 weeks after the start date.

Select the Compare to past checkbox.

From the Past time range list, select Custom.
Specify the same length of time as the current time range. Be sure that time range ends before you launched the bid strategy.

The scorecard below the performance summary graph shows the change in performance.

Tips:

To drill down and see metrics for ad groups or keywords, click the Ad groups or Keywords tab.

Compare similar campaigns or compare by geography

Compare similar campaigns

Compare campaigns managed by a Search Ads 360 bid strategy to similar campaigns that are not managed by a bid strategy (or that are managed by some other bidding system). For example, apply a bid strategy to 10 campaigns that advertise women's apparel, and compare performance to 10 campaigns that advertise similar men's apparel.

Compare by geography

If you have campaigns with the same keywords and ads but are targeted to different geographic regions, you can apply a Search Ads 360 bid strategy to campaigns in one region, but not the other.

For example, consider a company that sells bicycles and bicycle parts across the US. If the company has separate campaigns for each state in the US, the company can do the following:

Put the campaigns for New York, New Jersey, and Pennsylvania in a bid strategy.

Compare performance for the two sets of campaigns. Note that if the two regions historically perform at different rates (for example, an average of 15% more conversions in the more heavily populated region), the company needs to determine the proportional difference and apply the proportion to the comparison.

Requirements

To ensure an accurate comparison, wait until you've met all of the following requirements:

Wait 6 weeks after launching the Search Ads 360 bid strategy, and 4 weeks after making any significant changes to the target. (If you haven't made any changes since launching, you can run the comparison 6 weeks after launching. If you changed the target 3 weeks after launch, you can run the comparison 7 weeks after launch.)

Click volume: minimum of 10,000 total clicks for the campaigns in the bid strategy and 10,000 total clicks for the campaigns that are not in the bid strategy.

Position: It's preferable to compare campaigns with an average position above 2.0.
However, position constraints are not recommended when comparing performance.
That is, you'll get the most accurate comparison if your campaigns are naturally achieving an average position above 2.0 without using bid strategy constraints to force the 2.0 average.

ROI targets: For bid strategies with CPA, ERS, or ROAS targets, make sure the campaigns in the strategy are achieving within 10% of targets.

From the View menu that appears just below the tabs, select one of the following:

Performance if you're comparing a bid strategy with a clicks or position goal.
In addition, if you're comparing the position goal, add the Position column to the report.

Action if you're comparing a bid strategy with a CPA target.

Sales if you're comparing a bid strategy with a ROAS or ERS target.

Click the time-range selector that appears in the upper right corner of the page and select a timeline that meets the suggested requirements.

Use a filter to display only the campaigns that are in your bid strategy. For example, apply this filter:Bid strategy equals ERS - 6%

Make a note of the metrics you'll use for your comparison.
For example, note the ERS, number of transactions, and amount of revenue.

Clear the filter. Then create another filter that displays the similar campaigns that are not managed by the bid strategy. Make a note of the same metrics that you recorded for bid strategy and compare the results.